Controlling Russian Olives within Cottonwood Gallery Forests along the Middle Rio Grande Floodplain (New Mexico)

The diverse riparian and wetland plant communities of the Rio Grande floodplain have virtually disappeared following a century of flood control and channelization that drastically changed the river’s natural hydrologic regimes (Crawford and others 1993). Today, remnant gallery forests of Fremont cottonwood (Populus deltoides v. wislizeni) are all that remain, and even these are being replaced by non-native Russian olives (Eleagnus angustifolia) and saltcedar (Tamarisk spp). In 1998, the Pueblo of Santa Ana of central New Mexico developed a comprehensive program that includes the removal of these two exotic species and the restoration of native vegetation communities on the floodplain located within reservation. In this note, we highlight our efforts to control Russian olive in an 80-acre (32-ha) cottonwood gallery forest on the reservation. In the 1920s, shade-tolerant Russian olive began to appear in the Middle Rio Grande floodplain. Today it is the co-dominant tree, along with Fremont cottonwood, in the gallery forests (Hink and Ohmart 1984). These mixed stands form dense, fireprone thickets that often become monospecific stands of Russian olives because of vigorous root-sprout growth following a fire. One of Santa Ana’s goals is to remove Russian olive